Development and Delivery: Live Streaming Technologies at NAB Show 2017

Live production is quite literally the oldest television technique. Visitors to the recent NAB Show in Las Vegas might have enjoyed the exhibit by the Museum of Broadcast Technology, which showed cameras from a time when it was barely possible to record electronic images for later playback. Until the late 1950s, the brutally unforgiving world of live production was just about the only option. The difference between then and now is the cost of the equipment (generally lower) and the sheer number of different audiences that can now be served by streaming operations of every scale.

Interest in streaming at NAB Show this year represented every point on that scale. At the top, we find Akamai's demonstration of liveOrigin using NBC Sports material. Akamai's Media Services Live solution delivers 24/7 live/linear online video capabilities to support OTT video service providers, broadcasters and telcos that are operating full-time television channels online. The recently announced update will improve streaming quality, getting it that much closer to the quality of traditional broadcast television. Media Services Live includes four new components, together known as liveOrigin, that offer broadcast-quality ingest, low latency, a self-healing network, and monitoring and reporting.

The particular focus in liveOrigin is on reducing latency, the delay between a live event occurring and images of that event being shown to the viewer. The key interest here is in second-screen material, which a viewer might be watching on a cellphone or tablet alongside a conventional live television broadcast. Excessive delay—often many tens of seconds with current streaming solutions—can wreck the synchronization between the broadcast and the second screen, even to the point of spoiling moments of excitement.

In the more pocket-sized world, we find BoxCast's all-in-one streaming solution. BoxCaster Pro is a $1,000 device little larger than its 4.3-inch LCD monitor. It bridges traditional SDI- or HDMI-based production systems to streaming distribution, allowing a conventional camera or switcher output, as well as balanced XLR audio, to be easily distributed over the network. The latest revision, demonstrated at NAB Show, adds 4K HDR pictures at 60 fps, and mitigates the enormous bandwidth requirements of those pictures by implementing the advanced HEVC codec, which can often halve the bit rate required for a given level of image quality. BoxCast offers different annual pricing plans based on streaming features.

With the bandwidth required to transmit images only growing with the industry's embrace of ever-increasing resolution and frame rates, the topic of compression codecs is worth looking at more closely. HEVC was devised to provide double the effectiveness (the same image quality for half the bit rate, or double the quality for the same bit rate) while taking no more than three times the computer horsepower to decode. This seems like a poor exchange until we realize that network bandwidth is currently more difficult to upgrade than receiving devices are, but either way, there are other options.

The royalty-free and open source AV1 codec, promoted by the Alliance for Open Media, has been shown to be up to twice as effective as H.264, while, crucially, avoiding the patent and licensing issues of the widely used H.264 standard; it is also designed to be 25 percent more effective than HEVC. At NAB Show, Alliance for Open Media member Bitmovin conducted the first AV1 live streaming demo, delivering a 1080p image at a relatively tiny 1.5 Mb/s in what the company calls "broadcast quality."

Developing a new codec, though, is in some ways the easy part. The challenge is in deploying that codec, which may involve replacing the deployed base of set-top boxes and cellphones. Software is easier to update than hardware, and VP9 is already widely available in web browsers; whether AV1 follows suit when the standard is finalized (perhaps later this year) remains to be seen. V-Nova, another show exhibitor, has been promoting its Perseus codec for some time. The company emphasizes both its effectiveness and the fact that it's cleverly designed to be retrofitted, via firmware updates, into a wide range of already-deployed set-top boxes.

Also relying heavily on the sorcery of video compression, JVC's PB-CELL200 ProHD Portable Bridge is an expansion of work that's been done in the past in pursuit of streaming broadcastable video over cellphone infrastructure. This objective is on the very cusp of practicability, with the bandwidth of cellular networks rising to meet the falling bandwidths required for good video given modern compression technology. The PB-CELL200 is able to bond several cellular connections to provide reliable bandwidth for really good video, and links wirelessly to nearby JVC cameras via a Wi-Fi transceiver that plugs into each camera's USB port. Cellular transmission is hugely desirable given the vast cost of satellite uplinks.

With its XDCAM Air service, Sony also demonstrated an interest in transporting program material over cellphone infrastructure. It does several things—the company describes it as a "comprehensive ENG workflow platform"—but one feature that's directly relevant to streaming is XDCAM Pocket, which uses a smartphone's LTE connection to stream video. Even though it'll probably work best in urban areas with good cellphone coverage, it's almost certainly the start of the inevitable evolution to cameras that can uplink from anywhere without requiring much by way of external resources. The writing for satellite trucks, at least in areas with good cellphone coverage, is on the wall.

While in past years Nokia's presence at NAB Show primarily supported its mobile communications business, its 2017 exhibits focused on the OZO 360° video camera. Nokia announced OZO's update to OZO+, as well as new features in OZO Live, Nokia's scalable 3D 360 real-time VR solution. OZO Live provides real-time stitching of OZO's eight synchronized 2K x 2K image sensors, making live streaming of the 360° video sphere possible. Since OZO produces 4K video, streaming the results requires either a lot of bandwidth or very clever encoding.

Haivision showed its KB 4K encoder/transcoder, which features hardware-accelerated HEVC encoding to fuel the highest quality streaming events, supporting up to 4K viewing. It offers four 3G-SDI or IP video inputs supporting one 2160p60 channel (or up to four 1080p60 channels). It encodes video with high effectiveness, meaning a favorable ratio of image quality to bit rate, using the HEVC (H.265) codec. This is widely considered necessary to make video work well on virtual reality headsets.

With strategic partner Wowza Media Systems, Haivision announced the founding of the SRT Alliance and the open-source availability of SRT, a video transport protocol to enable the delivery of high-quality and secure, low-latency video across the public internet.

Sling Media's SlingStudio serves the rather different market of those independent streamers who've graduated from a webcam for video acquisition and have learned that compelling content requires sophisticated production technology. SlingStudio is a multicamera production device that lets users record, monitor and edit four HD video inputs from up to 10 connected cameras and smartphones. It can output live video to streaming services like Facebook Live and YouTube, and simultaneously record to a USB hard drive, USB SSD or SD card for postproduction.

The hub device presents its user interface on an iPad, avoiding the need for a hardware control surface. Cameras connect wirelessly, and there's even a wireless HDMI transmitter module for roaming cameras. SlingStudio is capable of some graphics and audio mixing, as well as integration with Adobe Premiere Pro for later editing. As with many all-in-one systems, limitations stem less from the capability of the system and more from the operator's ability to manage everything at once.

Another force in the area of portable live streaming, LiveU showcased its LU600 portable transmission unit, which is now field-upgradeable to support H.265/HEVC streaming. The appliance is capable of bonding internet connections for increased bandwidth and better overall quality. Perhaps the most interesting part of LiveU's approach is the cloud-based titling and character generation; these tasks are performed on a remote server as opposed to the local device. Additionally, LiveU collaborated with content creators BeTerrific to produce a live broadcast from the convention, as they had done at CES 2017 earlier in the year.

Livestream sponsored and hosted the Live Streaming Pros' NAB Show broadcast, which was captured with Livestream's Mevo live event camera. The soda can-sized camera, which began shipping last year, uses a 4K sensor with a very wide lens to achieve a 150° overall field of view, relying on the excess resolution of the sensor to allow reframing and live switching of views. Clever functions include face recognition, which allows the camera to follow a presenter using its ability to move the region of interest within the 4K image. While the camera was previously controllable only from an iPhone, the company announced significant software upgrades at the show. Android support is now expected by the end of the summer, as well as 4K recording, 1080p streaming and integration with both YouTube Live and NewTek's NDI network video protocol.

Introduced last year, NDI (Network Device Interface) technology allows multiple video systems to identify and communicate with one another over IP, and to encode, transmit and receive many streams of high quality, low latency, frame-accurate video and audio in real time.

Speaking of which, NewTek announced TriCaster TC1 at the show. This update offers up to 16 inputs of up to UHD 60p resolution via NDI, a technology that hovers on the border between live streaming and IP video production. TriCaster itself is a production switcher and graphics system of enormous capability—more than capable of producing results similar to the most elaborate broadcast television productions if the user can press buttons fast enough—but the real trick in the latest release is NDI.

While manufacturers and various standards bodies debate the future of standardized video-over-IP for live production, NewTek has created and released NDI, which does much the same thing—give or take a couple of technical caveats—right now, and for a lot less money. While it's likely that a more general standard will eventually be established, NDI has made advances like the 16-input TriCaster possible, and support for the protocol is becoming common on production equipment from vendors across the industry.

One such product is BirdDog's Studio NDI, which brings us back to live TV. In some ways it's a simple concept, if not a simple device to make; Studio NDI sits on a camera and converts its SDI or HDMI output to NDI for transmission across cheap, available Ethernet infrastructure. The real benefits are in the details, though, with the bidirectional nature of network connections providing support in the future for features such as tally lights, return video and talkback. It's a neat trick and probably exactly the sort of thing NewTek had in mind when they published the NDI specification. The relevance to those early days of live studio television, with no second take to cover mistakes, is hard to miss. ve